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2 SheetsSheet 1. B. WHITMORE.

' Lifting Bridge.

No. 225,775. Patented Mar. 23, I880.

2 Sheets-Sheet 2.

E. B. WHITMORE. Lifting Bridge.

No. 225,775. Patented Mar. 23, I880.

UNITED STATES PATENT OFFICE.

ENOS B. WHITMORE, OF ROCHESTER, NEW YORK.

LlFTlNG-BRIDGE.

SPECIFICATION forming part of Letters Patent No. 225,775, dated March 23, 1880.

Application filed June 19, 1879.

' To all whom it may concern:

Be it known that I, ENOS B. WHITMORE, of Rochester, in the county of Monroe and State of New York, have invented a new and useful Improvement in Lifting-Bridges, which improvement is fully set forth in the following specification and accompanying drawings, in which Figure 1 is a plan Fig. 2, a side elevation viewed as indicated by the arrow z in Fig. 1. Fig. 3 is an end elevation viewed as indicated by arrow 2 in Fig. 1; Fig. 4, a partial end elevation; Fig. 5, a contracted plan of pipes, 850.; Fig. 6, a modification in the manner of placing the machinery; and Figs. 7 and 8 are details.

My invention relates to that class of bridges known as hoist or lift bridges, being one in which the bridge-body is raised vertically and in horizontal positions from its bearings to allow the passage of crafts beneath; and it consists in the employment of various novel devices hereinafter fully explained, by means of which the bridge is suspended and operated.

In the drawings, A is the bridge proper, C the canal or stream bridged, and B the banks of the same.

The bridge proper, A, shown is of ordinary construction, intended for a road or street, consisting of two longitudinal supporting-girders, b, resting near their ends upon cross-beams d, there being a carriage-way between and sidewalks f on the outside of the girders.

At the ends of the beams d cables to are attached, which pass over pulleys 9, supported at the tops of four vertical standards or towers, h, firmly based at the corners of the bridge. From the pulleys g the cables pass downward through openings l at the bases of the towers, around pulleys a, and are wound upon drums 7c, inclosed within cavities or pits G, formed in the banks of the canal as shown in Figs] and 3.

From this description it will be understood that if the drums are simultaneously and correspondingly rotated by some suitable motor the bridge-body will be raised and lowered vertically and evenly, all of its positions in its ascent and descent being parallel and horizontal.

The standards h are each composed of two vertical sections or wings joined at their edges in a vertical line and forming a right angle, as clearly shown in section at the lower righthand corner in Fig. 1.

w are counter-weights, designed to partially balance the weight of the bridge-body, secured to the cables a, and move vertically within the dihedral angles of the said standards as the bridge is carried up or down,pits a being provided, into which they may descend when the bridge is at its uppermost position.

At the edges of the angles of the standards there are vertical guide-posts secured, which form guides or tracks up and down which the bridge may move, there being rollers t provided to roll along said tracks, as shown. The rollers t are hung in the ends of roller holders or stems t, which rest horizontally in hangers b, secured one under each of the four corners of the bridge, the said stems being provided with springs s, whichv urge the rollers against the guides. The stems t are placed so that their axes coincide with the diagonal broken lines which approximate the resultant lines of horizontal expansion and contracttion of the material of the bridge from changes of temperature, which expansion and contraction between the heat of summer and cold of winter amount to about one and one-eighth inch in one hundred feet for rolled iron. By inspecting Fig. 7, Sheet 2, the philosophy of thus placing the roller-holders 26 will be better understood.

Let the parallelogram F represent the bridge in plan; then the expansion along the line L :0 would carry the corner a to x, and the simultaneous expansion along the line P so would carry it from w to 00 the resultant of which two motions at right angles with each other would be the diagonal a: m, which is the actual line of motion of the corner :20, resulting from expansion and contraction. The roller-holders being placed to coincide with these diagonal lines, the rollers it will be moved directly toward or from the axes of the guides 11, which is the object sought.

The springs s are designed to yield as the bridge expands and return as it contracts, and hold the rollers at all times fairly against the guides with a yielding pressure, on account of which the bridge is permitted to move up and down smoothly and without hitching or cramping.

Any convenient motive power applied to rotate the drums may be employed in operating the bridge, such as steam, water, horses, 850., the motor shown being a water-engine placed within a chamber, G, in the bank of the canal, of which d is the cylinder, containing a water-tight piston, to which is secured a vertical rack, 0, arranged to engage the teeth of a pinion, t, of the drum-shaft c, a like engine being placed under the other end of the bridge to rotate the drum at that point. If water under pressure be let under the pistons the drums will be rotated and the bridge raised. If, when the bridge is up, the inflow of water be stopped and an outflow from the cylinders caused, the bridge, by its weight, will descend to its bearings.

In Figs. 1 and 5, 0 is a pipe lying across the bottom of the canal and connecting the bottoms of the two cylinders d.

p is a pipe leading from a street-main, joined to the pipe 0 at a point equidistant between the cylinders by which they are each equally supplied with water.

4", Figs. 2 and 3, is a gate in the pipe 1), by means of which water may be either let onto or cut off from the cylinders.

0 is an outlet-pipe connected with the pipe 19 between the gate 4" and the cylinders, and is provided with a similar gate, m, by means of which the outflow from the cylinders may be either caused or stopped. If the gate m be closed and the gate 1' opened water will flow through the pipes p and 0 to the cylinders. If the gate 4' be closed and an opened the water will flow outward through the pipes 0,12, and 0.

U is a vertical rod designed to slide endwise, connected at its lower end with the stem a of the gate 1", and proyided at its upper end with an arm, 0, projecting horizontally out over the bridge, and a foot-rest, c, for the bridge-tenders use.

6 is another vertical rod, similar to the rod 4;, and similarly connected to the gate on by means of the stem 8, and operated bya lever, f, within reach of the bridge-tender.

When the bridge is to be raised the attendant presses the rod '0 downward, which opens the gate 1", and when nearly up the bridge comes in contact with the arm 0, as shown in Fig. 3, and again raises the rod 1), which closes the gate and automatically stops the bridge. If the bridge is to be lowered the lever f is pressed downward, which opens the gate m, allowing the water in the cylinders to escape through the pipe 0, and when nearly down the bridge presses upon the upper end of the rod 0, as shown in Fig. 3, again closing the gate m, when the bridge again stops automatically.

The gates r and m are designed to be formed so that the former will be closed when the rod set forth, it will be seen that the operations of the motors, though placed one at either end of the bridge, are both alike under the control and management of the bridge-attendant stationed at one end thereof, and that both motors are alike automatically operated by the bridge itself from the same point.

' Should either end of the bridge, on account of less friction or other cause, move more rapidly than the other, it may be retarded and the motion of the ends equalized by regulating the relative flow of water to the respective cylinders, which may be done by reducing or increasing the water-way leading to one or the other of the same, as the case may require. To effect this I introduce gates h in the pipe 0, it being designed to place one between each cylinder and the point of junction between the pipes 19 and 0, by means of which the relative flow of water toward each cylinder may be regulated. These gates are to be set by experiment to cause the bridge to always keep substantially level, and they may also be used to determine the rate of motion at which the bridge shall move up and down by increasing or decreasing the rate of flow of water to and from the motors.

Fig. 4- shows an end view of the bridge raised to its uppermost position above the approaches 7c. Chains a are suspended from its under side, which support horizontal rods or bars 12 for the purpose of guarding the approaches to the bridge when the same is raised. When the bridge is lowered these guard-bars descend into pits under the bridge made to receive them, and, being attached to chains, are capable of folding into comparatively small spaces.

The towers It may be made ornamental and formed to completely conceal the weights and pulleys g, and, with the weights, they may be made cylindrical, hexagonal, or of other form, and should their presence in sight be objectionable they may be placed wholly below the level of the bridge-floor and out of sight, as shown in Fig. 6, by extending legs D down from the corners of the bridge to a sufficientdistance, and to the bottoms thereof attaching the cables and track-rollers t, the tracks, weights, pulleys, drums, motors, 820., being correspondingly depressed.

By this plan of bridge all superstructures in the form of elevated supporting-trusses spanning the canal are dispensed with, and the counter-weights are kept comparatively low and away from over the bridge, together adding to simplicity and cheapness of construction. There are no fixed or moving parts over the bridge to fall and endanger passersby, and the motors and machinery being sub stantially concealed, and not offensive to the sight, or present to frighten horses.

It will be understood that if the pipe 19, leading from the main, were joined to the pipe 0 nearer to one of the cylinders than the other, the nearer cylinder would, on account of there being less friction in that direction, receive water more rapidly than the other, and consequently carry that end of the bridge up faster than the other end was moving.

To insure the cylinders being equally supported I connect the pipe 12 to the pipe 0 at a point equidistant from each, and join the said pipes at right angles, so the water flowing into the pipe 0 may turn with equal facility toward either cylinder.

I claim as my invention.

1. In combination with a vertically-lifting bridge, A, and vertical guides p, the rollers or parts It, moving upon said guides, and held against the same by a yielding force, substantially as and for the purpose set forth.

2. In combination with the lifting-bridge A and guides 29, roller-holders 15, so placed that the slight horizontal motion given the rollers t by the natural expansion and contraction of the bridge, due to changes of temperature, shall be in direct lines toward or from the axes or center longitudinal lines of the said guides, for the purpose set forth.

3. In combination with a vertically-lifting bridge, A, guides 19, and rollers t, the hangers l, roller-holders t, and springs s, substantially as shown.

4. The lifting-bridge body A, the towers h, and cables to, the latter arranged to pass over the towers and downward through their bases to an operating-drum within the abutment, all combined to operate as and for the purpose set forth.

5. In combination with a lifting-bridge, A, and its operating mechanism, counter-weights w, secured upon the operating-cables a midway thereof, substantially as shown and described.

6. The combination of the lifting-bridge A, gate-rods v and e, stems a and .9, starting and stopping gates r and m, and pipes o, p, and 0, arranged substantially as shown and described.

7. The vertically-lifting bridge A, with standards h, having pits a and passage-ways b, the cables a, wheels g, weights w, pulleys a, and drums la, in combination with suitable motors for operating the same, substantially as shown and described.

8. In combination with the lifting-bridge A,

the motors d, arranged one beneath each end of the-bridge, and connected by a common feed-pipe and actuated by the same headpressure therethrough, and provided with a pipe, 12, the latter having a starting and stopping gate or valve, 1', and an outlet-pipe, 0, provided with another starting and stopping gate, m, the pipe 0 being connected to the inflow-pipe p at a point between the gate 7' and the motors, and all arranged to operate as and for the purpose herein set forth.

9. In a vertically-lifting bridge constructed as shown and described, the motors d and pipes 0 p 0, with their respective gates h 1" m, in combination with the rods 1; e and arm 0, all arranged to operate substantially as and for the purpose herein set forth.

10. In combination with a vertically-lifting bridge, the operating-motors d and counterweights to, arranged to act conjointly upon the same cables, for the purpose of lifting the bridge, substantially as shown and described. 11. A vertically-lifting bridge, A, provided with regulating devices IL for the motors, by means of which the bridge may be kept at all times substantially level while moving upward or downward, as described, and its rate of motion upward and downward increased or diminished at pleasure.

- E. B. WHITMORE. Witnesses:

IRA A. HEBBARD, HENRY E. WHITE. 

